Suction cleaner



Feb. 25, 1941. R. s. BoYLE 'sucTIoN CLEANER Filed Feb. 2, 1958 ATTORNEY Patented 25e-19,41 f 'l i Robert S. Boyle, Akron, Ohio, assig'norto Hoover Company, North Canton, Ohio, a corporation of Ohio Application February 2, 193s, serial No. 188,234

- scum This invention relates to improvements insuctiori cleaners and more particularly to means for maintaining the. nozzle of a suction cleaner substantially at `a constant height above the surface of the oor covering to be'cleaned regardlegis of. its quality, texture or other characteristics.. It 'has been the standard practice to equip suction cleaners with some form of mechanism or device for adiusting the'height of the nozzle for different grades of carpet to compensate for varying depths to whichv 'the wheels will sink into the nap depending on the depth and thickness thereof.

The'. object of the present invention is to provide a. suction cleaner with a carpet contacting member in the form of a flat plate capable of gliding over the surface without appreciable penetration in the carpet nap while supporting the 20 load which otherwise would tend to depress the forwardV or nozzle portion of the cleaner.-

A preferred embodiment of the invention is fully disclosed in the accompanying drawing in which:

Figure 1 is a general view in side elevation of a suction cleaner equipped with the nozzle height regulating means, with portions shown in vertical section---as'taken on line I-I of Figure 2;

Figure 2 is a bottom plan View of the cleaner'` 30 showing the contact plate; and

Figure 3 is a detail view in vertical section taken on^line 3-3' ofFigure 1. l*

The suction cleaner'herein disclosed is typical of any standard handle-maneuvered device and 33 consisting generally of a casing 'I.lnc1uding a g nozzle portion 2 extending transversely of its forward end and having a nozzle chamber with a 'downwardly opening suction mouth `2a4 extending substantially thev fullwidth of the-nozzle por- 4o'tion.A v'

and'rear wheelsliv and 4,4. respectively, both pairs being preferably :lournalled on suitable' bearings so located that the casing is supported in 45 a'siibstantially lhorizontal position with the suction mouth 2a parallel with and elevated slightly above the surface of the oor covering to be cleaned. As clearly shown in Figure 2, the front wheels 3,3 are located immediately to the rear 50 of the nozzle chamber and just inwardly from the side edges of the casing I.- `The rear wheels 4,4 preferably form a caster including a bracket 5 fixed to the underside of the casing I just forwardly of its rear end.

To complete the cleaner assembly. the casing 'rhecasing i issupported upon o'f-fr'ont l (ci. -1si I includes {,a centrally located fan chamber 6 ini which is mounted a motor-driven fan 1, the motor (not shown) beingV supported upon the cleaner casing I with its axis arranged vertically and enclosed within a removable hoodor cover 5 8. A handle 9 has pivotal connection with the vcleaner'casing andpreferably near its rear end, the pivotal mounting for said handle being par- ,tially enclosed by the rear end portion o1' the" cover 8. And flna.l1y,a bag forms the dirt collect- 10 ing receptacle 'I0 and has detachable connection -with the flanged outlet II from the fan chainber 6. The design and operation of the cleaner being more or less conventional, Aneed not be describedin further detail. -15 In designing a'suction cleaner, it is obviously desirable to distribute the load as uniformly as possible between the front and rear wheels, but with the force of suction acting at the nozzle, v there is a denite tendency for thefront wheels to sink into the surface of a rug or carpet to a greater depth than the rear wheels and thus bring the nozzle closer to the carpet surface than is proper for effective cleaning. This tendency can be counteracted somewhat by-using wheels of A relatively wide tread surfaces at the front pf the cleaner. butv equally eilective is the utilization of wheels of standard size which offer relatively little resistance to carpetpenetration and combine therewith a carpet contacting plate so located -to offer a substantial support for the` forward portion of the cleaner and to establish a horizontal plane below which the suction mouth may not -be depressed regardles's'of the @depth of lnap,tex

ture orother characteristics of the carpet being cleanedp'f W. .v f

Such a plate is herein disclosed, being preferably located beneath the casing- I, immediately to the rear of the nozzle chamber and occupying x the transverse space between'the front supporto -ing wheels 1.3.1 Thiscarpet'contactingmember .has'the forni of -a rectangular` plate ori shoefof Valslightly dishedor concave form duetoiaislight bevel around the edges thereof; -Thelbottom'tacefof theplate I2, exclusive' ofthe upwardly inclined 45 or beveled edge portions thereof, lies in and determines a horizontal plane extending substantially midwaybetween the plane of the suction mouth of 'the nozzle and the horizontal plane defined by the contact points ot the wheels with 5o the floor covering.

Now, if the cleaner is resting upon a hard surface as in Figure 1. the plate I2 .will clear the surtace by a fraction of an inch. wy slr. while the suction mouth will be moed above the door aurlo face a somewhat greater distance, say of an inch.. But should :the cleaner beplaced upon a carpet of medium thickness. the penetration of the supporting wheels into the carpet nap would bring the plate i2 into contact with the carpet surface and it would now support the load which previously was carried on the front wheels I'. 3 and without appreciable penetration into the carpet nap. In other words, the bottom surface of the plate l-I would noat substantially on the top surface of the carpet nap and thereby maintain .the plane of the suction mouth a predetermined distance above andout of contact with the carpetsurface. y

It is to be noted however, that the fixed distance separating the parallel planes of the suction mouth and the contact plate Il may not determine the actual spacing of the suction mouth above the carpet surface due to the factY that there is another factor to be taken into consideration, namely, the penetration of the rear wheels 4, l into the carpet surface.- Consequently, even assuming that the plalte I2 in contact with the carpet surface limits the vertical displacement of 4the forward portion of the cleaner, the sinking of the rear wheels into the carpet nap causes the" cleaner to -tilt bodily upon the plate l2 and which, due to the convexity of its bottom face, acts as a rocker, permitting the nozzle portion to be elevated slightly and thus compensate for the penetration of the front wheels. Thus it is the combined load supporting ability of the plate |12 plus the bodily tilting movement of the cleaner on the plate as a fulcrum that maintains the suction mouth of the nozzle substantially at the proper height for effective cleaning regardless of the type and characteristics of the particular carpet being cleaned.

It follows therefore, that the primary purpose of the plate i2 is .to support the forward portion of the cleaner in gliding contact with the surface of the carpet while lthe sinking of the rear wheels into .the carpet nap introduces a certain addition-al compensating effect calculated to bring about a substantially constant -nozzle height for a considerable range of different carpet characteristics. It perhaps should be mentioned in this connection that 'the suction of a cleaner in operation lifts the carpet into sealing contact with the mouth of the nozzle, so that it is incorrect to consider the nozzle as being spaced above the carpet surface but rather with relation to some fixed horizontal plane such 'as .the floor surface. duce a virtual gliding of the forward portion of the cleaner over .the carpet surface (usually combined with a slight tilting of the nozzle by virtue of the penetration of the rear wheels into the carpet nap), thereby compensating for the initial penetration of the front wheels 3, l.

Having determined the size and location of the l plate l2, the manner in which it 'is attached to In any case. the plate l2 functions to ,pro-

.forms the passage extending forwardly from the entrance to the fan chamber to the nonle chamber, said passage also housing the belt I4 which drives a lindric shaped agitator il, located in `time noule chamber, from a pulley It located at the lower end of an extended hub portion of the fan 'I+ A simple method of attaching the Plate lltothebottomplatellistouseseveral L- shaped pieces l'l screwed or riveted to the top of the plate -I2 and to the-vertical side faces of the bottom platel Il which is itself somewhat dish-shaped or concave from frontto rear. If desired. however, the plate I1 and bottom plate il might readily be made in a single piece. Having disclosed a practical application of the invention. I claim: l

1. In a suction cleaner, the combination of a body having a nozzle at its forward end and supporting wheels iournalled on fixed bearings mounted adjacent its front and rear ends, and a substantially dat plate mounted on the underside of said body adjacent said nozzle and disposed at a predetermined distance below the plane of the mouth of said nozzle, said plate having a downwardly facing carpet contacting surface of an area sufficient .to support the adjacent portion of said body upon .the surface of the carpet with the nozzle elevated at a substantially uniform height above the carpet surface irrespective of its quality and texture.

2. In a'l suction cleaner, the combination of a casing having a nozzle at itsforward end and pairs of supporting wheels journalled on fixed bearings mounted at its front and rear ends and positioned to support said'nozzle at a predetermined height above the floor level, and a flxed plate mounted on the underside of said casing between said pairs of wheels and den'ing a horizontal plane intermediate the plane of said nozzle mouth and the plane defined -by the points of contact of the wheelswith the floor surface and having an area sufficient to support the casing with the mouth of said nozzle elevated above the surface of the carpet and at a substantially uniform height regardless of the tex-ture and thickneas of the carpet being cleaned. t

3. In a suction cleaner, the combination of -a casing having. a nozzle at its forward end and pairs of supporting wheels journalled on fixed bearings mounted at its front and rear ends, said front wheels being positioned to support said nozzle at a predetermined height above the floor level, and a fixed plate mounted on the underside of sald'caaing adjacent said nozzle and having a substantially nat bottom face defining a horizontal plane disposed intermediate the planes of said nozzle mouth and the plane defined by the points of contact of said`wheels with the floor surface, said plate having an area suflicient to support the forward portion of said casing upon the oanpet surface with the mouth of said nozzle elevated at a substantially uniform height above the surface of the carpet regardless of its texture and the thickness of its nap.

ROBERT S. BOYLE. 

